I've noticed that David Powers' "Muhammad is not the father of any of your men" gets cited around the place. I bought a copy on Amazon a few years ago, but I'll admit - I couldn't get to grips with it and therefore, I didn't review it (like I still haven't reviewed any Wansbrough anywhere). Today I ran across a critique by Yasin Dutton. This is "Old Light On A New Problem: The Kalāla
Verses Revisited" in Journal of Semitic Studies
59.2 (Aut. 2014), 357-76.
Dutton has written several very-good articles on what's now being called "Codex Parisino-petropolitanus" aka "BNF 328a", pointing out that it might be Himsi (if you're a classicist, Emesan). Dutton also wrote a book titled "The Origins of Islamic Law" but then, as Wael Hallaq has pointed out, all scholars of Islamic law write one of those, and it's never about the origins of fiqh
So, Dutton seems to be good on the Arabic script; but once upon a time overconfident in his own abilities in fiqh. Here he is critiquing Powers on the interplay between the two. I copied this from the JSS website.
The publication of D.S. Powers’ Muḥammad is Not the Father of Any of Your Men: The Making of the Last Prophet again raises questions about the meaning of the word kalāla and, by extension, the history of the Qur’ān and Islamic inheritance law. In this article, we reconsider the verses where kalāla is mentioned, and, in particular, Powers' contention that the word originally read kalla, meaning daughter-in-law, and not kalāla. We first question his supposed manuscript evidence for this assertion, preferring to read instead an unambiguous instance of the word kalāla. Secondly, we question his grammatical understanding of the word, basing ourselves on Mālik's Muwaṭṭa', which suggests that we should understand the word as a maṣdar (verbal noun) rather than a substantive. We also cast doubt on Powers' argument that it was only as a later, post-Prophetic development that the Prophet came to be considered — or was ‘made’ — the Last Prophet. Rather, we consider the linguistic and literary evidence to point to the clear conclusion that Muhammad was always considered, from his lifetime, as the Seal of the Prophets in the sense of being the last of them.